This invention relates generally to the field of seating and more particularly to vehicle seat assemblies. Previously, most vehicle seating involved the use of a frame having an arrangement of springs upon which a padding such as foam rubber was positioned. This seat is then covered with a fabric or other sheet material which is attached to the frame. In a co-pending application Ser. No. 437,715, filed Oct. 29, 1982, commonly assigned, a seat assembly is disclosed having a foam encapsulated load supporting fibrous matrix stretched between laterally spaced frame members of a seat. In this seat assembly the foam pad is molded in place onto the load supporting fibrous matrix that is prepositioned on the frame. Thus, the foam encapsulating covers both the fibrous matrix or fabric sheet and the side rails of the frame upon which the seat cushion is to be mounted.
The seat assembly of the above mentioned copending application must be positioned partially inside a mold cavity where the foam is injected to expand the foam pad over the fabric matrix and portions of the frame.
In contrast, the present invention provides a vehicle seat cushion suspension assembly that will be mounted on a frame having laterally separated side rails but which is produced without the necessity of premounting the fabric shett between the side rails of a vehicle seat frame. The result is a vehicle seat cushion suspension assembly that is more versatile and simpler to produce. In addition, the elimination of the requirement for a mold to accommodate the seat frame permits the mold to be smaller and more compact as well as enabling one mold to be utilized for a variety of seating configurations. The frame thus is not a constraint to the mod configuration in the present invention.
The vehicle seat cushion suspension assembly of this invention for carrying seating loads on a vehicle seat having laterally separated side rails comprises a flexible elastic woven fabric material, generally rectangular in shape, having a foam body integrally molded and bonded thereto. The load supporting fabric sheet is formed of woven flexible elastic filaments. A foam cushion body is integrally molded and bonded to the fabric such that the fabric and the foam body molded together act in concert to elastically support seating loads when the assembly is mounted on and positioned between side rails of a vehicle seat frame. The fabric material effectively transfers the loads from the cushion to the side rails while the foam in the body functions to lock all of the filaments together to provide for the desired distribution of seating loads throughout the sheet and avoid areas of stress concentration.
The vehicle seat cushion suspension assembly of this invention applies equally well to the formation of the vehicle seat back. A seat back assembly having laterally separated side rails may also have a flexible elastic fabric supported between them with a foam body integrally molded and bonded thereto that act together to support seating loads on the seat back.
The seat cushion suspension assembly according to the present invention is produced in a foam mold. The flexible woven fabric sheet is mounted inside one-half of a hollow mold, the other half of the mold is closed over the first half, the expandable foam is injected into the mold cavity. As the foam expands and encapsulates the fabric contained therein the fabric is effectively bonded to the foam body formed therein. The mold is then opened and the foam body with fabric attached is removed. The fabric sheet, with the foam body integrally molded and bonded thereto can then be attached to the side rails of a seat frame.
In addition, once the foam body with the fabric sheet bonded thereto is removed from the mold a seat trim sover may then be bonded to the foam body. This is done by takin a preformed seat trim cover having a complimentary shape to that of the outside surface of the foam body, coating the cover or the body with adhesive, and positioning the seat trim cover onto the frame body in complimentary relation and then applying heat and pressure which bonds the seat cover to the foam pad or body.
The resulting assembly can then be mounted on a seat frame such that the fabric sheet is suspended between side rails of the frame and the edges of the seat cover may be wrapped around and attached to the underside of the seat frame thus completing the seat assembly.
Further objects, features, and advantages of this invention will become apparent from a consideration of the following detailed description when taken in conjunction with the appended claims and accompanying drawings.